1st grade · Math · Unit 1 of 14
Numbers to 20
Count, compare and build numbers
What your child practices
Counting, ordering and comparing numbers to 20, and seeing teen numbers as 1 ten and some ones.
Arizona Academic Standards learning standard: 1.NBT.A.1 · counting, reading and representing numbers
How we explain it
Children can open this short lesson before they practice.
- Numbers 11 to 19 are 1 ten and some ones.
- Count on from 10: 11, 12, 13.
- The bigger number comes later when you count.
Example: How many tens and ones are in 17? 17 is 1 ten and 7 ones. 10 + 7 = 17. Answer: 1 ten and 7 ones
Numbers to 20 in Arizona
In the Arizona Academic Standards, this is unit 1 of 14 in 1st grade Math, before Make 10.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Source: Arizona Department of Education
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
What number goes where the ? is?
- 5
- 12
- 10
10
Hint: Look at the number just before the ?. What comes after 9?
Question 2
Build the number 17.
Build it with tens rods and ones cubes.
17
Hint: 17 is 1 ten and 7 ones.
Question 3
Tap the numbers from smallest to biggest.
- 8
- 20
- 6
- 5
5 → 6 → 8 → 20
Hint: Start with the smallest number, 5.
Question 4
How many 🎈?
🎈🎈🎈🎈🎈🎈🎈🎈- 8
- 4
- 11
8
Hint: Touch each one as you count. Say the numbers out loud!
Question 5
What number do the blocks show?
- 18
- 16
- 19
18
Hint: A ten stick is 10. Then count on 8 more.
Question 6
How many 🎈?
🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈🎈- 18
- 20
- 14
18
Hint: Touch each one as you count, and keep going past 10!